Nestled deep in a picturesque highland valley beside a clear, cool stream – or a ‘burn’ as they’re known locally - the tiny hamlet of Edradour has all the ingredients for the perfect whisky: water filtered through peaty hills, plump grain from Scottish fields, and generations of know-how.

Distillery owner Andrew Symington enjoys nothing more than taking in the heady aromas in his six-and-a-half-thousand cask whisky warehouse – and occasionally sampling the product.

“You’ve got like sugared almonds here, little bit of nutty maltiness, and then you’ve got all the dried fruits you find, so it’s Christmas cake. Orange peel, raisins. Mmm, very warming,” he said with a satisfied smile.

Symington watched the Brexit vote unfold with alarm. Sixty percent of his whisky goes to Europe.

“Europe currently is a network of 28 countries, all the tax warehouses are linked so it’s very much about ease of shipment and very little paperwork. If we’re not in that European club then of course things may change, they could impose tariffs on us,” he said.

For Edradour, the vote to leave the EU has come a critical time. Symington is investing $6.6 million to expand the distillery and meet increasing demand. The number of tourists visiting the distillery is growing by the week. His concerns over Brexit uncertainty are tempered by an unexpected boost in sales.

“Since then of course the pound has fallen 13 or 14 percent, so this is making a big impact too because our products are now much cheaper, and of course they’re more affordable in Europe,” he said.

Whisky is Scotland’s third biggest industry, bringing in more than $6 billion to the British economy – larger than shipbuilding or steel. Europe is one of its best customers and losing access to the single market would be painful for the industry and for the Scottish economy.

Such concerns are driving renewed calls from Scotland’s first minister for her country to break away from the rest of the United Kingdom.

“I for one am not interested in it,” said Symington. “She will only cause untold problems if she splits from England. I would like to stay in the EU for sure, but I think if we’re not in the EU we must be united as a United Kingdom.”

In centuries past, the ancient hills around Edradour have witnessed bloody battles over Scotland’s independence.

England’s armies may be long gone but the matter is, perhaps, not yet settled. The fight over Scotland’s future is igniting once more – and the artisans producing the country’s most famous export are on the frontline.